 main(List<String> args) {
  print("数字类型声明");
  num salary=5000;

  print("收入:"+salary.toString());

  salary=7500;

  print("收入1"+salary.toString());


  salary=10000.58;
  print(salary);


  //int类型只能时整数
  int money=160000;
  print("收入2:\$$money");

  //double 类型只能时小数
  double price=40.6;

 
  
}